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2 ReviewMycorrhiza are symbiotic relationships between plant roots and soil inhabiting fungiPlants pass photosynthate to the fungi in return for mineral nutrients, particularly nitrogen and phosphorousFormed by most land plants

5 Why are we interested in depth?Niche partitioningStudies in monocultures of dual infection hosts have shown guild wide niche partitioning (Neville et al. 2002)Nutrient cyclingArbuscular mycorrhizae are thought to be responsible for phosphate mining, and may be a chief component of phosphorous additions to older plant communities (Smith and Read 2008)

6 ObjectivesCompare percent root length colonized in each guild along depth and the ratio of the twoCompare the root length of each guild along depth and the ratio of the two \

7 HypothesesPercent root length colonized will be less in the deeper soils than in the shallow in both guilds, the AM/EM ratio will increase with depthColonized root length will be less in the deep soil, but the AM/EM ratio will increase with depth

8 Field methods Roots were collected by the shoestring crew in fall 2010Shallow soils were collected using 10cm soil coresA 20cm power core was used to collect deep soilsSoils were separated into horizons based on visual inspection

9 Methods Root length is estimated using grid intersectionEctomycorrhizal colonization is estimated by using the proportion of those intersections which crossed ectomycorrhizal root tips compared to colonized rootTo estimate Arbuscular mycorrhizal percentage <1mm diameter roots are cut into 2mm section and stained, slides are prepared and examined at 400x magnification and the presence or absence of arbuscular mycorrhizal features is noted

11 Root length per area of soil by mycorrhizal guildResultsRoot length per area of soil by mycorrhizal guild

12 ResultsGreater colonization in shallow soils regardless of guild (p<0.001)Greater root length in shallow soils regardless of guild (p=0.016)No change in the ratio of percent colonization between guilds across depth (p=0.46)Change in the ratio of root length between guilds across depth in one stand

13 Future work Post treatment mycorrhizal measurements-Decrease in mycorrhiza tionin response to fertilizationUse molecular methods to determine variation in mycorrhizal diversity across depthDevelopment of new AM primers may lead to a unified methodology for sampling mycorrhiza of both guilds